Glass lens and method of treating the same



Dec. l5, 1925. 1,566,127

v w. RUNDQUIST GLASS LENS AND METHOD 0F TREATING THE .SAME

Filed Nov. 3. 1924 "Willian ,ulzdyuid gwuentoz .lll

Patented Dec. 15, 1925.

UNITED STATES PATENT OFFICE.

GLASS LENS AND METHOD 0F TREATING THE SAME.

Application filed November 3, 1924. Serial' No. 747,591.

To fil/ whom t 'may concern:

Be it known that I, TILLrAM RUNDQUIST, a citizen of the United States of America, residing at Elgin, in the county of Kane and State of Illinois, have invented certain new and useful Improvements in Glass Lenses and Methods of Treating the Same, of which the following is a specification.

My invention relates to improvements in glass lenses or the like, and to methods of treating and preparing the same.

An important object of my invention is to 'provide a lens so treated that all glare will be eliminated without consequent loss of illumination.

Another object of my invention is the provision of a new and improved method of treating lenses. Y

@ther objects and advantages of my in- Avention will be apparent during the course of the following description.

In the accompanying drawings which form a part of this specification and wherein like characters of reference denote like or corresponding parts throughout the same Figure 1 is a front elevation of an automobile headlight provided with my improved lens;

Figure 2 is a section on the line 2-2 of Figure l; and

Figure il is a sectional view of a portion of a lens, illustrating more or less diagrammatically the method of treatment.

In the drawings wherein for the purpose of illustration is shown a preferred embodiment of my invention, the numeral l0 designates an automobile headlight of the usual construction having a bulb 1l arranged therein and provided with a lens 12 arranged in front of said bulb.

Heretofore it has been customary to treat the surface of lenses by sand blasting, for the purpose of cutting down the glare, but this treatment is such that a frosting or coating is formed on the surface of the lens, which prevents the light from getting through, vor in other words, bottles it. This sandblasting is done by projecting the sand upon the lens at an angle perpendicular to the surface of the lens, as illustratn ed by the dotted arrows A in Figure 8 of the drawing. Because of this angle, it is impossible to exert any great amount of pressure on the sand because of breaking the lens.

I have discovered, however, that if coarse particles of silica of a uniform size are projected against the inner surface of the lens under great pressure and at an angle substantially less than 90 degrees with respect to the surface of the lens to be treated as illustrated by the arrows B in Figure 3, the frosting does not appear on the finished lens. By directing the silica blast at an angle less than a right angle, great force may be employed, without breaking the lens. The large uniform particles of silica projected in a slanting stream, groove the surface of the lens and affect the very texture of the glass by crushing the line cells or globules within the lens. Flakes are cut out slantingly which force the light to pass sideways through the lens.

When the coarse particles of silica strike the glass with great force, the interior, as well as the surface, is affected, substantially regular crystals being formed within the glass by reason of the uniformity in size of the silica particles. The sides of these crystals, within the glass, are snowy white, and the light passing therethrough is changed from a clear to a milky white. These crystals, together with the iiakes cut out of the surface, sift the white light and diffuse it. The light is not bottled up, but is all allowed to go through the lens. The coating formed by a perpendicular stream of fine sand, or sand containing some fine particles is not formed by my process of treating the glass because of the uniformity of the size of the silica particles, the great amount of pressure, and the direction in which the silica is projected against the surface of the glass.

Heretofore it has been usual to use what is known by the trade as pressed glass for nonglare lenses. With my method of treatment, however, it is possible to use drawn glass without a'ny danger of glare. By treating the inside surface of the lens, the cause of glare is attacked at its source, and the crystals throw beams of nonglaring light through the remainder of the clear glass.

Lenses treated with my improved method, cut out all glare with no consequent loss of illumination and therefore portions of clear7 untreated glass are rendered unnecessary, thereby dispensing with a dangerous feature of many types of lenses which so bottle up the light that it is necessary to let the light out Without diffusing it7 in portions of the glass.

While l have shown and described my invention as applicable to automobile lenses. it is to be understood that l do not limit myself to this use, as have discovered it useful in window lighting and other arts.

aving described my invention what I claim and desire to protect by Letters ljatent is:

l. rl`he method of treating glass lenses which consists in directing a blast of silica at an angle to the surface of the lens.

2. The method of treating lenses which consists in projecting a stream of uniform particles of silica in a slanting direction upon the surface of the lens.

3. The method of treating lenses which consists in projectinga slanting stream of coarse particles of silica With a great amount of force, upon the surface of the lens, to form substantiallyv uniform crystallized surfaces Within the texture of the lens by breaking'up the globules of the glass.

4. A. lens having its surface treated with silica blasting whereby the globules of the glass are broken up into regular crystals, each of said crystals being adapted to throw a separate beam of light, thereby doing away With all glare.

Y. i lens having its inner surface treated to forni crystallized surfaces radiating towards the interior of the lens, said crystallized surfaces being of a color to change the light to a milky color.

G. A lens having its inner surface treated to form slantingi' grooves on the surface and crystallized surfaces radiatii'ig` towards the interior of the lens. whereby light goingthrough the lens will be broken up and diffused.

l. l lens having one of its surfaces smooth and the other surface treated to form crystallized surfaces radiating towards the interior of the lens.

ln testimony whereof l ailix my signature.

VVILLAM RUNDQUIST. 

